Air conditioner for hot air furnaces



Aug. 17, 1954 w. 'r. SMITH AIR CONDITIONER FOR HOT AIR FURNACES 2 Sheets -Shee't 1 Filed April 12, 1951 INVENTOR Aug. 17, 1954 w. T. SMITH AIR CONDITIONER FOR HOT AIR FURNACES 2 Sheets-Sheet 2 Filed April 12, 1951 INVENTOR tion.

Patented Aug. 17, 1954 UNITED STATES PATENT OFFICE AIR CONDITIONER. FOR HOT AIR FURNACES William T. Smith, St. Louis, Mo.

Application April 12, 1951, Serial No. 220,553

'7 Claims. 1

The present invention relates to an air conditioner for hot air furnaces and it consists in the combinations, constructions and arrangements of parts herein described and claimed.

Generally there is provided an air conditioning apparatus for conventional hot air type furnaces and the invention contemplates the mounting of cooling coils containing refrigerant in either the inlet duct or the outlet duct or ducts of a furnace or, in one embodiment of the invention in both the inlet and outlet ducts. In another form of the invention the cooling coils are placed in the conventional air chamber surrounding the firebox of the furnace. Novel provision is made for leading off to the outer atmosphere fumes which may escape from the conventional refrigerant pipe and novel means is also provided for collecting condensate. It is also contemplated that in practice the coil containing portion of the apparatus may be substituted for an equal length of either the inlet duct or the outlet duct of the conventional furnace structure.

It is accordingly an object of the invention to provide an apparatus of the character set forth which may be quickly and easily installed as a part of the conventional hot air type furnace installation.

Another object of the invention is the provision of novel means for regulating the humidity of air passing through a device of the character set forth.

Another object of the invention is the provision of novel means, in a device of the character described, for collecting and dissipating fumes of refrigerant which may accidentally emanate from a cooling pipe forming a part of the inven- Other and further objects of the invention will become apparent from a reading of the following specification taken in conjunction with the drawing, in which:

Figure 1 is a front elevational view, partly broken away, of an embodiment of the invention shown installed in a conventional hot air type furnace installation,

Figure 2 is an enlarged sectionalview, partly in elevation, of an air cooling unit forming part of the invention,

Figure 3 is a fragmentary sectional View taken substantially along line 3-3 of Figure 2,

Figure 4 is an enlarged sectional view taken substantially along line 6-4 of Figure ,2,

Figure 5 is a view similar to Figure 4 but showing a modified form the invention may assume,

Figure 6 is a view similar to Figure l but showing a modification thereof,

and an outlet duct ll.

partly in section, illustrating a further modified form the invention may take.

Referring more particularly to the drawings, there is shown therein a conventional hot air type furnace provided with an outer casing Ill and conventional doors ll, l2 and I3 and interiorly provided with a firebox Hi and an air-heating chamber 15 which lies between the walls It of the casing and the outer side of the firebox M.

The furnace is provided with an inlet duct it? In Figure 1 there is shown as supplanting an ordinary length of the duct is a cylindrical casing 18 having a much greater diameter than the diameter of the duct it and having a coil of composite pipe generally indicated at l9 mounted therein adjacent the inner wall thereof.

The pipe 19 may take a number of forms but in Figures 2, 3 and 4 it is shown as having an outer hexagonal pipe 26 and an inner circular pipe 2! whose outer side is contiguous to the six facets of the inner wall of the pipe 20. The inner pipe 2| extends through the lower end of the casing is to form an inlet pipe 22. The composite pipe l9 extends through the upper end of the casing, as indicated at 23, and the inner ipe 22 protrudes through an elbow 24 formed in the outer pipe 25 to provide an outlet pipe 25.

Another form the pipe l9 may assume is illu trated in Figure 5 wherein the inner pipe 2| is interconnected with an outer pipe 26 by a plurality of spaced radially extending ribs 21.

. Extending through the top of the casing H) is a spray nozzle 26 which is connected by means of a pipe 26 to a source of water supply and centrally and vertically mounted in the top of the casing H3 is a shaft all provided with a pulley 3| which is connected by means of a belt 32 to a pulley 33 carried by a motor shaft 3!; of a motor 35 which is, in turn, mounted upon a bracket '35 fastened to the outer wall of the casing ill. The shaft 38 is extended downwardly into the interior of the casing is and has a conventional fan affixed thereto, such fan being conventional and not shown in the drawings.

in this form of the invention, it will be apparent that air is led in through the duct l6 and is cooled by passing over the composite pipe it! and that the pipe 2| is adapted to contain refrigerant being in effect an expander coil of a compressor-condenser-expander type refrigeration system, by way of example, and that the pipe 22 will therefore lead from, for example, the conventional condenser coils of such system while the pipe 25 will lead to the intake or low side of the conventional compressor. It will be apparent that between the pipe 2| and the pipe 28 there is provided air spaces 31 and likewise between the pipe 2! and the pipe 26 there is provided air spaces 38. In either case the air spaces 31 or 38 will lead any refrigerant gases which may escape from the pipe 2i upwardly and outwardly through the elbow 24 which will thereupon lead the same to the outside atmosphere where they will not pollute the air passing through the furnace. In this form of the invention there is provided at the lowermost portion of the casing iii a condensate pipe 39 provided with a goose neck 40 wherein water collecting on the inner walls or dripping from the composite pipe l9 will pass by gravity and be collected within the goose neck 40 from which it may be withdrawn by any conventional means. The thus cooled air will pass into the furnace l and will be supplied with additional moisture from the nozzle 28, the latter being preferably controlled by a hygrometer (not shown).

In the form of the invention shown in Figures 6 to 8, inclusive, wherein similar parts are given identical reference characters to those shown hereinabove, the casing I8 is provided with an outer casing 41 which is spaced therefrom and an insulating material 42 is placed between the casing 58 and M to prevent to a large degree heat from the surrounding area from being absorbed in the system.

Also, in this form of the invention it will be apparent that the duct It extends entirely through the casing l3 and that the pipe 2| is provided with no outer pipe as in the case of the outer pipes 213" and 26 illustrated in Figures l and 5. In this form of the invention the upper end of the casing 18 is provided with an outwardly extending pipe 43 provided at its outer end with an elbow at through which the outlet pipe 25 extends and it will be apparent that gaseous refrigerant which may escape through the pipe 2i will be collected in that space between the outer side of the duct I ii and the inner wall of the casing I8 and will eventually emanate through the elbow 44 whence it will be led to the outside atmosphere as heretofore described with regard to the elbow 24. Also in this form of the invention there is provided an additional cooling unit which is generally indicated at 45 in Figure 6 and whose operation is identical with that heretofore described with regard to the devices shown in Figures 1 and 5, by way of example.

In Figure 9, instead of placing the cooling unit within the inlet or outlet ducts H or I! as the case may be, the evaporator coil connected to the pipe 22 from the condenser is positioned in the air chamber l5.

In all cases it will be apparent that the apparatus herein shown and described may be quickly and easily attached to and made a part of a conventional air heating type of furnace installation by placing the units in either the inlet duct or the outlet duct or in both or, in another form of the invention, in the conventional air heating chamber surrounding the firebox of the furnace. It will also be apparent that the humidity of the air passing through the unit will be lessened by the collection of moisture in the traps 48 and that moisture may be added when necessary by means of the nozzle 2B.

While only certain forms of the invention have been shown and described herein, it will be readily apparent to those skilled in the art that many minor modifications may be made without departing from the spirit of the invention or the scope of the appended claims.

What is claimed is:

1. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides of said housing, the provision of means for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing and having an inlet pipe and an outlet pipe extending through said casing, means for collecting moisture from the interior of said casing, and means for leading to the outer atmosphere refrigerant gas emanating from said cooling coil.

2. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides of said housing, the provision of means for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing and having an inlet pipe and an outlet pipe extending through said casing, means for collecting moisture from the interior of said casing, and means for leading to the outer atmosphere refrigerant gas emanating from said cooling coil, and means for humidifying the cooled air.

3. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a fire box mounted in said housing in spaced relation to the sides of said housing, the provision of means for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said'means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing and having an inlet pipe and an outlet pipe extending through said casing, means for collecting moisture from the interior of said casing, means for leading to the outer atmosphere refrigerant gas emanating from said cooling coil, and means for humidifying the cooled air, said means for humidifying the cooled air comprising a spray nozzle mounted in the upper end of the housing, and a pipe for supplying water to said nozzle.

4. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides of said housing, the provision of means for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing and having an inlet pipe and an outlet pipe extending through said casing, means for collecting moisture from the interior of said casing, and means for leading to the outer atmosphere refrigerant gas emanating from said cooling coil, said last-named means including an outer pipe surrounding in spaced relation the convolutions of the cooling coil, said outer pipe having an elbow exterior of said casing, said inner pipe extending through said elbow, and said elbow con nected to the outside atmosphere.

5. An apparatus of the character described comprising, in combination with a furnace hav ing a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides of said 1 housing, the provision of means for cooling, hu-

midifying and dehumidifying air passing through said ducts and said housing, said means including a cooling coil mounted in said housing about said firebox and having an inlet and an outlet pipe extending through said housing, and means for dissipating gaseous refrigerant emanating from said cooling coil.

6. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides: of said housing, the provision of means for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing tending through said casing, means for collecting moisture from the interior of said casing, 30

means for leading to the outer atmosphere refrigerant gas emanating from said cooling coil, and an insulating cover for said casing.

7. An apparatus of the character described comprising, in combination with a furnace having a housing, inlet and outlet ducts extending from said housing, and a firebox mounted in said housing in spaced relation to the sides of said housing, the provision of means associated with said furnace housing and ducts for cooling, humidifying and dehumidifying air passing through said ducts and said housing, said means including a cylindrical casing connected into one of said ducts, a cooling coil mounted in said casing and having an inlet pipe and an outlet pipe extending through said casing, means for collecting moisture from the interior of said casing, means for leading to the outeratmosphere refrigerant gas emanating from said coil, the said cylindrical casing and described assemblies constructed as a unit to substitute for and take the place of a section of conventional air duct of like measurements, and constituting a kit for easy and economical conversion of conventional hot air furnace, blower-equipped, to a year-round air conditioning unit.

References Cited in the file of this patent UNITED STATES PATENTS Dodge Dec. 27, 1938 

